Well - I am not impressed...
If the EU wanted to do something useful, they'd have dealt with this, not fecked about with hoovers.
Me and mate are adding teh second layer of insulation in the dormer. This time, I decided, as it's the finish layer, it might be suitably paranoid of me to use pink fire rated expanding foam (Screwfix NoNonsense) as "fire rated" seems like a good idea.
Anyway, long story short - to see exactly what the differences were, we took a small lump (1x2" sort of lump) of this, plus a couple of old bits of other foams outside.
Now - I was expecting "fire rated" to mean "itumescent" and to not only not support combustion, but to char over or something.
Well - it does not support combustion - but it does burn. Rather like celotex. Hold a flame to it, it burns, take flame away, it goes out.
The yellow foam I tried actually was not much worse - it did flare for a bit, but seemed to char and go out.
However, some green foam went like a bloody firework. Needless to say, I really was unimpressed.
I have no idea what the other makes were - I used the yellow stuff, so it was *probably* Screwfix no nonsense.
The green stuff was used by the roofers in odd places to make sure the celotext stayed in place. Dunno what make that was - but this was 4 years ago.
The mitigating factor is 95% is being covered by more celotex and plasterboard. However, there are odd bits in the eaves - which I have been cutting out where they've formed blobs - and I've already cleared it where it enveloped electrical cables - just because it seemed like a bad idea. Most cables pass through the insulation in PVC conduit which does not support combustion - but there are cables that come straight up from the walls past the insulation.
I'm of a mind, after trimming back any excesses, to give the exposed parts a coat of in-tumescent paint.
But WHY are they being allowed to sell stuff that ignites and supports combustion? I thought we'd got past that with polystyrene and furniture foam.
Glad I switched to pink foam...